package com.hhly.rabbitmq.rpc;


import java.io.IOException;

import com.hhly.rabbitmq.RabbitMQUtil;
import com.rabbitmq.client.AMQP;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Consumer;
import com.rabbitmq.client.DefaultConsumer;
import com.rabbitmq.client.Envelope;

public class RPCServer {
	
   static final String RPC_QUEUE_NAME = "rpc_queue";
   
   public static void main(String[] args) throws Exception {
	   final Channel channel = RabbitMQUtil.getChannel();
	   channel.queueDeclare(RPC_QUEUE_NAME, false, false, false, null);
	   channel.basicQos(1);
	   Consumer consumer = new DefaultConsumer(channel) {
           @Override
           public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws IOException {
               AMQP.BasicProperties replyProps = new AMQP.BasicProperties
                       .Builder()
                       .correlationId(properties.getCorrelationId())
                       .build();

               String response = "";
               System.out.println("thread"+Thread.currentThread().getName());
               try {
                   String message = new String(body,"UTF-8");
                   int n = Integer.parseInt(message);

                   System.out.println(" [.] fib(" + message + ")");
                   response += fib(n);
               }
               catch (RuntimeException e){
                   System.out.println(" [.] " + e.toString());
               }
               finally {
                   channel.basicPublish( "", properties.getReplyTo(), replyProps, response.getBytes("UTF-8"));
                   channel.basicAck(envelope.getDeliveryTag(), false);
               }
           }
       };
       channel.basicConsume(RPC_QUEUE_NAME, false, consumer);
   }
   
   private static int fib(int n) {
	    if (n == 0) return 0;
	    if (n == 1) return 1;
	    return fib(n-1) + fib(n-2);
	}
}
